Bland-Altman Limits of Agreement

Problem

Return the limits of agreement [mean(d) - z*sd(d), mean(d) + z*sd(d)] for paired measurements d = a - b, using the sample standard deviation. Return [0.0, 0.0] when fewer than two pairs are given or lengths differ, and [mean(d), mean(d)] when all differences are equal.

Hint

Most differences should fall between the two limits.

Test cases

case 1

in: [[10,12,14],[9,11,13],1.96]

expected: [1,1]

case 2

in: [[10,12,14,16],[9,11,14,15],1.96]

expected: [-0.22999999999999998,1.73]

case 3

in: [[5,6,7],[4,6,8],1.645]

expected: [-1.645,1.645]

case 4

in: [[1],[2],1.96]

expected: [0,0]

case 5

in: [[],[],1.96]

expected: [0,0]

Starter codePython

def bland_altman_limits(a, b, z_crit):
    # Your code here
    pass

5 test cases · run your code against them in the editor